Theorem disjabrexf 33225

Description: Rewriting a disjoint collection into a partition of its image set. (Contributed by Thierry Arnoux, 30-Dec-2016.) (Revised by Thierry Arnoux, 9-Mar-2017.)

Hypothesis

Ref	Expression
disjabrexf.1	⊢ Ⅎ𝑥𝐴

Assertion

Ref	Expression
disjabrexf	⊢ (Disj 𝑥 ∈ 𝐴 𝐵 → Disj 𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}𝑦)

Distinct variable groups:   𝑥,𝑦,𝑧   𝑦,𝐴,𝑧   𝑦,𝐵,𝑧

Allowed substitution hints:   𝐴(𝑥)   𝐵(𝑥)

Proof of Theorem disjabrexf

Dummy variables 𝑖 𝑗 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		nfdisj1 5083	. . . 4 ⊢ Ⅎ𝑥Disj 𝑥 ∈ 𝐴 𝐵
2		nfcv 2922	. . . . 5 ⊢ Ⅎ𝑥𝑦
3		disjabrexf.1	. . . . . . . . . . 11 ⊢ Ⅎ𝑥𝐴
4	3	nfcri 2914	. . . . . . . . . 10 ⊢ Ⅎ𝑥 𝑖 ∈ 𝐴
5		nfcsb1v 3870	. . . . . . . . . . 11 ⊢ Ⅎ𝑥⦋𝑖 / 𝑥⦌𝐵
6	5	nfcri 2914	. . . . . . . . . 10 ⊢ Ⅎ𝑥 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵
7	4, 6	nfan 1931	. . . . . . . . 9 ⊢ Ⅎ𝑥(𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)
8	7	nfab 2928	. . . . . . . 8 ⊢ Ⅎ𝑥{𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)}
9	8	nfuni 4873	. . . . . . 7 ⊢ Ⅎ𝑥∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)}
10	9	nfcsb1 3869	. . . . . 6 ⊢ Ⅎ𝑥⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵
11	10	nfeq1 2937	. . . . 5 ⊢ Ⅎ𝑥⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦
12	2, 11	nfralw 3309	. . . 4 ⊢ Ⅎ𝑥∀𝑗 ∈ 𝑦 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦
13		eqeq2 2772	. . . . 5 ⊢ (𝑦 = 𝐵 → (⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦 ↔ ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝐵))
14	13	raleqbi1dv 3329	. . . 4 ⊢ (𝑦 = 𝐵 → (∀𝑗 ∈ 𝑦 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦 ↔ ∀𝑗 ∈ 𝐵 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝐵))
15		vex 3454	. . . . 5 ⊢ 𝑦 ∈ V
16	15	a1i 11	. . . 4 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 → 𝑦 ∈ V)
17		simplll 787	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → Disj 𝑥 ∈ 𝐴 𝐵)
18		simpllr 788	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑥 ∈ 𝐴)
19		simprl 783	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑖 ∈ 𝐴)
20		simplr 781	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑗 ∈ 𝐵)
21		simprr 785	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)
22		csbeq1a 3860	. . . . . . . . . . . . . 14 ⊢ (𝑥 = 𝑖 → 𝐵 = ⦋𝑖 / 𝑥⦌𝐵)
23	3, 5, 22	disjif2 33223	. . . . . . . . . . . . 13 ⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ (𝑥 ∈ 𝐴 ∧ 𝑖 ∈ 𝐴) ∧ (𝑗 ∈ 𝐵 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑥 = 𝑖)
24	17, 18, 19, 20, 21, 23	syl122anc 1406	. . . . . . . . . . . 12 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)) → 𝑥 = 𝑖)
25		simpr 490	. . . . . . . . . . . . . 14 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → 𝑥 = 𝑖)
26		simpllr 788	. . . . . . . . . . . . . 14 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → 𝑥 ∈ 𝐴)
27	25, 26	eqeltrrd 2861	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → 𝑖 ∈ 𝐴)
28		simplr 781	. . . . . . . . . . . . . 14 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → 𝑗 ∈ 𝐵)
29	22	eleq2d 2846	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = 𝑖 → (𝑗 ∈ 𝐵 ↔ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵))
30	25, 29	syl 18	. . . . . . . . . . . . . 14 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → (𝑗 ∈ 𝐵 ↔ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵))
31	28, 30	mpbid 235	. . . . . . . . . . . . 13 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)
32	27, 31	jca 521	. . . . . . . . . . . 12 ⊢ ((((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) ∧ 𝑥 = 𝑖) → (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵))
33	24, 32	impbida 813	. . . . . . . . . . 11 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → ((𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵) ↔ 𝑥 = 𝑖))
34		equcom 2050	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑖 ↔ 𝑖 = 𝑥)
35	33, 34	bitrdi 290	. . . . . . . . . 10 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → ((𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵) ↔ 𝑖 = 𝑥))
36	35	abbidv 2826	. . . . . . . . 9 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = {𝑖 ∣ 𝑖 = 𝑥})
37		df-sn 4585	. . . . . . . . 9 ⊢ {𝑥} = {𝑖 ∣ 𝑖 = 𝑥}
38	36, 37	eqtr4di 2813	. . . . . . . 8 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = {𝑥})
39	38	unieqd 4879	. . . . . . 7 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → ∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = ∪ {𝑥})
40		unisnv 4886	. . . . . . 7 ⊢ ∪ {𝑥} = 𝑥
41	39, 40	eqtrdi 2811	. . . . . 6 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → ∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = 𝑥)
42		csbeq1 3849	. . . . . . 7 ⊢ (∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = 𝑥 → ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = ⦋𝑥 / 𝑥⦌𝐵)
43		csbid 3859	. . . . . . 7 ⊢ ⦋𝑥 / 𝑥⦌𝐵 = 𝐵
44	42, 43	eqtrdi 2811	. . . . . 6 ⊢ (∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} = 𝑥 → ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝐵)
45	41, 44	syl 18	. . . . 5 ⊢ (((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) ∧ 𝑗 ∈ 𝐵) → ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝐵)
46	45	ralrimiva 3154	. . . 4 ⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑥 ∈ 𝐴) → ∀𝑗 ∈ 𝐵 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝐵)
47	1, 12, 14, 16, 46	elabreximd 33154	. . 3 ⊢ ((Disj 𝑥 ∈ 𝐴 𝐵 ∧ 𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}) → ∀𝑗 ∈ 𝑦 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦)
48	47	ralrimiva 3154	. 2 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 → ∀𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}∀𝑗 ∈ 𝑦 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦)
49		invdisj 5088	. 2 ⊢ (∀𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}∀𝑗 ∈ 𝑦 ⦋∪ {𝑖 ∣ (𝑖 ∈ 𝐴 ∧ 𝑗 ∈ ⦋𝑖 / 𝑥⦌𝐵)} / 𝑥⦌𝐵 = 𝑦 → Disj 𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}𝑦)
50	48, 49	syl 18	1 ⊢ (Disj 𝑥 ∈ 𝐴 𝐵 → Disj 𝑦 ∈ {𝑧 ∣ ∃𝑥 ∈ 𝐴 𝑧 = 𝐵}𝑦)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1569   ∈ wcel 2144  {cab 2738  Ⅎwnfc 2907  ∀wral 3076  ∃wrex 3086  Vcvv 3450  ⦋csb 3846  {csn 4584  ∪ cuni 4866  Disj wdisj 5069

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1827  ax-4 1841  ax-5 1942  ax-6 1999  ax-7 2040  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2212  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1572  df-fal 1582  df-ex 1812  df-nf 1816  df-sb 2099  df-mo 2564  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-ral 3077  df-rex 3087  df-rmo 3365  df-rab 3413  df-v 3452  df-sbc 3739  df-csb 3847  df-ss 3896  df-dif 4047  df-in 4091  df-un 4151  df-nul 4279  df-sn 4585  df-pr 4587  df-uni 4867  df-disj 5070

This theorem is used by:  measvunilem  34892